The data of 16o national meteorological observatory stations including the long-term monthly temperature data in China were analyzed to study the seasonal variation of the spatial temperature structures across China i...The data of 16o national meteorological observatory stations including the long-term monthly temperature data in China were analyzed to study the seasonal variation of the spatial temperature structures across China in the past half century. It is found that temperature structures differ between seasons： a latitude temperature pattern in winter and a landform temperature pattern in summer, which indicate that the effect of landform on temperature structure is much stronger in summer than that in winter and the effect of latitudinal temperature is much stronger in winter than that in summer. The mechanisms of the seasonal difference in temperature structures are also discussed in this paper.展开更多
The main factors that influence the temperature field of frozen subgrade were analyzed.The experimental equipment for simulating frozen subgrade was built up,and the declining regulating tubes were placed at the foot ...The main factors that influence the temperature field of frozen subgrade were analyzed.The experimental equipment for simulating frozen subgrade was built up,and the declining regulating tubes were placed at the foot of the embankment. By means of this equipment two simulating experiments of controlling temperature filed of frozen sub- grade were carried out in the laboratory.One method is to collect natural cold energy,and the other one is to collect natural cold energy ccompanied by artificial refrigeration simultaneously.The result indicates that the latter is an ef- fective method for maintaining the stability of the frozen subgrade.展开更多
Either from the perspective of the finite supply capacity of global resources and energy,or from the perspective of global environment restrictive conditions,developing countries can not repeat the old development roa...Either from the perspective of the finite supply capacity of global resources and energy,or from the perspective of global environment restrictive conditions,developing countries can not repeat the old development road of developed countries,either in view of the international pressure China is currently facing,or in view of China's own resources endowment and stages of development,we must actively face such a challenge of climate change.We must recognize that the issue of climate change may be a great restraint to the present and future eco-social development,and may also be an important driving force and new opportunity to push forward the transformation of development pattern,to take a new road of industrialization and to realize sustainable development.This demands us,on the one hand,to take the Scientific Outlook of Development as the guide to make efforts to control the emission of greenhouse gases and continuously increase the capability of adapting to climatic change,and set up the overall plan to respond to climate change of our country,and on the other hand,we should unswervingly take the road of sustainable development,save energy,optimize energy structure and strengthen biological protection in slowing and adapting to climate change.展开更多
Band structure and component content are the key factors for determining the activity of semiconductor heterojunction. In this study, a novel Bi5O7I/BiOBrxI1-x heterostructure was synthesized by a simple hydrobromic ...Band structure and component content are the key factors for determining the activity of semiconductor heterojunction. In this study, a novel Bi5O7I/BiOBrxI1-x heterostructure was synthesized by a simple hydrobromic （HBr） acid etching method through transforming partial of Bi5O7I to I ion doped BiOBr （BiOBrxI1-x） at room temperature without adding extra dopant. Both the band structure and component content of Bi5O7I/BiOBrxI1-x alter with the additive HBr acid. The Bi5O7I/BiOBrxI1-x （S3.0） sample exhibits the best photocatalytic activity, 6 times higher than that of pure Bis071, for the degradation of methyl orange under visible-light （2 〉 420 nm）. The activity enhancement of Bi5O7I/BiOBrxI1-x is primarily ascribed to the improved separation efficiency of photocharges, originated from the adjustable band structure and component content, The significant findings of this paper provide a facile way to construct highly efficient semiconductor heterojunction via playing the synergetic effect of adjustable band struc- ture and component content for purifying organic pollutants in wastewater.展开更多
基金supported NKBRSF,PR China,No.2002CB111507The National Key of Science and Technology,No.2004BA508B22+2 种基金the Chinese National Natural Science Foundation(90302006,90511026)the Hundred Talents Program(2004401,KZCX3-SW-339)of the Chinese Academy of Sciencesthe Project for 0utstanding Scientists(40121101)of the National Natural Science Foundation of China.
文摘The data of 16o national meteorological observatory stations including the long-term monthly temperature data in China were analyzed to study the seasonal variation of the spatial temperature structures across China in the past half century. It is found that temperature structures differ between seasons： a latitude temperature pattern in winter and a landform temperature pattern in summer, which indicate that the effect of landform on temperature structure is much stronger in summer than that in winter and the effect of latitudinal temperature is much stronger in winter than that in summer. The mechanisms of the seasonal difference in temperature structures are also discussed in this paper.
基金Projects 2002CB412704 supported by the National Key Basic Research and Development Foundation of the Ministry of Sciences and Technology of China KZCX1-SW-04 supported by the Knowledge Innovation Program of the Chinese Academy of SciencesSKLFSE200304
文摘The main factors that influence the temperature field of frozen subgrade were analyzed.The experimental equipment for simulating frozen subgrade was built up,and the declining regulating tubes were placed at the foot of the embankment. By means of this equipment two simulating experiments of controlling temperature filed of frozen sub- grade were carried out in the laboratory.One method is to collect natural cold energy,and the other one is to collect natural cold energy ccompanied by artificial refrigeration simultaneously.The result indicates that the latter is an ef- fective method for maintaining the stability of the frozen subgrade.
文摘Either from the perspective of the finite supply capacity of global resources and energy,or from the perspective of global environment restrictive conditions,developing countries can not repeat the old development road of developed countries,either in view of the international pressure China is currently facing,or in view of China's own resources endowment and stages of development,we must actively face such a challenge of climate change.We must recognize that the issue of climate change may be a great restraint to the present and future eco-social development,and may also be an important driving force and new opportunity to push forward the transformation of development pattern,to take a new road of industrialization and to realize sustainable development.This demands us,on the one hand,to take the Scientific Outlook of Development as the guide to make efforts to control the emission of greenhouse gases and continuously increase the capability of adapting to climatic change,and set up the overall plan to respond to climate change of our country,and on the other hand,we should unswervingly take the road of sustainable development,save energy,optimize energy structure and strengthen biological protection in slowing and adapting to climate change.
基金supported by the National Natural Science Foundation of China(51772118,51472005)State Key Laboratory of Structural Chemistry(20160014)+2 种基金Anhui Provincial Natural Science Foundation(1708085MB32)the Natural Science Foundation of Educational Committee of Anhui Province(gxyq ZD2016414,KJ2014B08)Innovation Team of Design and Application of Advanced Energetic Materials
文摘Band structure and component content are the key factors for determining the activity of semiconductor heterojunction. In this study, a novel Bi5O7I/BiOBrxI1-x heterostructure was synthesized by a simple hydrobromic （HBr） acid etching method through transforming partial of Bi5O7I to I ion doped BiOBr （BiOBrxI1-x） at room temperature without adding extra dopant. Both the band structure and component content of Bi5O7I/BiOBrxI1-x alter with the additive HBr acid. The Bi5O7I/BiOBrxI1-x （S3.0） sample exhibits the best photocatalytic activity, 6 times higher than that of pure Bis071, for the degradation of methyl orange under visible-light （2 〉 420 nm）. The activity enhancement of Bi5O7I/BiOBrxI1-x is primarily ascribed to the improved separation efficiency of photocharges, originated from the adjustable band structure and component content, The significant findings of this paper provide a facile way to construct highly efficient semiconductor heterojunction via playing the synergetic effect of adjustable band struc- ture and component content for purifying organic pollutants in wastewater.
